Omalizumab

The Basics

What is Omalizumab?

Used to treat moderate to severe persistent allergic asthma.

Brand names for Omalizumab

Xolair

How Omalizumab is classified

Anti-Allergic Agents, Anti-Asthmatic Agents

Omalizumab During Pregnancy

Omalizumab pregnancy category

Category N/ANote that the FDA has deprecated the use of pregnancy categories, so for some medications, this information isn’t available. We still think it’s useful to list historical info, however, given what a common proxy this has been in the past.

What we know about taking Omalizumab while pregnant

A registry study of XOLAIR exposure during pregnancy showed no increase in the rate of major birth defects or miscarriage. There was an increased rate of low birth weight among registry infants compared to infants in the other cohorts, despite average gestational age at birth; however, women taking XOLAIR during pregnancy also had more severe asthma, which makes it difficult to determine whether the low birth weight is due to the drug or the disease severity . There are risks associated with poorly or moderately controlled asthma in pregnancy [see Clinical Considerations]. Human IgG antibodies are known to cross the placental barrier; therefore, XOLAIR may be transmitted from the mother to the developing fetus. In animal reproduction studies, no evidence of fetal harm was observed in Cynomolgus monkeys with subcutaneous doses of omalizumab up to approximately 10 times the maximum recommended human dose (MRHD) . The estimated background risk of major birth defects and miscarriage for the indicated population(s) is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the US general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively. Clinical Considerations Disease-Associated Maternal And/Or Embryo/Fetal Risk In women with poorly or moderately controlled asthma, evidence demonstrates that there is an increased risk of preeclampsia in the mother and prematurity, low birth weight, and small for gestational age in the neonate. The level of asthma control should be closely monitored in pregnant women and treatment adjusted as necessary to maintain optimal control. Data Human Data A prospective cohort pregnancy exposure registry study conducted in the US from 2006 to 2018, included 250 pregnant women with asthma treated with XOLAIR. Of these, 246 patients were exposed to XOLAIR in the first trimester of pregnancy, and the median exposure duration was 8.7 months. The registry findings for applicable mother and infant subgroups were compared to age-adjusted frequencies in a disease matched external cohort of 1,153 pregnant women with asthma (without exposure to XOLAIR) identified from healthcare databases of residents in the Canadian province of Quebec, and referred to as the Quebec External Comparator Cohort (“comparator cohort”). Among applicable registry infants, the prevalence of major congenital anomalies (8.1%) was similar to that for infants in the comparator cohort (8.9%). Among applicable registry pregnancies, 99.1% led to live births, similar to 99.3% for the comparator cohort. There was an increased rate of low birth weight among registry infants (13.7%) as compared to the comparator cohort (9.8%); however, women taking XOLAIR during pregnancy also had more severe asthma, which makes it difficult to determine whether the low birth weight is due to the drug or the disease severity. The registry study cannot definitively establish the absence of any risk because of methodological limitations, including the observational nature of the registry, small sample size, and potential differences between the registry population and the comparator cohort. Animal Data Reproductive studies have been performed in Cynomolgus monkeys. There was no evidence of maternal toxicity, embryotoxicity, or teratogenicity when omalizumab was administered throughout the period of organogenesis at doses that produced exposures approximately 10 times the MHRD (on a mg/kg basis with maternal subcutaneous doses up to 75 mg/kg/week). Omalizumab did not elicit adverse effects on fetal or neonatal growth when administered throughout late gestation, delivery, and nursing.

Taking Omalizumab While Breastfeeding

What are recommendations for lactation if you're taking Omalizumab?

Because omalizumab is a large protein molecule with a molecular weight of 145,058, the amount in milk is likely to be very low and absorption is unlikely because it is probably destroyed in the infant’s gastrointestinal tract. The manufacturer reports that 186 infants have been breastfed during maternal omalizumab therapy, with no increase in infectious complications.

Maternal / infant drug levels

Because omalizumab is a large protein molecule with a molecular weight of 145,058, the amount in milk is likely to be very low and absorption is unlikely because it is probably destroyed in the infant’s gastrointestinal tract. The manufacturer reports that 186 infants have been breastfed during maternal omalizumab therapy, with no increase in infectious complications.

Possible effects of Omalizumab on milk supply

Relevant published information was not found as of the revision date.

Possible alternatives to Omalizumab

(Asthma) Benralizumab, Mepolizumab.